Delta Air Lines is investing in L.A.

The Atlanta-based carrier, the third-largest at Los Angeles International Airport, is adding 17 new flights to eight new destinations, boosting the number of seats from LAX by 12%.

In addition, Delta is teaming up with airport officials to invest $160 million in upgrades at its terminals, including adding a new luxury bar last summer at the Skyteam lounge. (Instead of helping themselves at a self-serve bar, members can now ask a friendly bartender to mix up a stiff drink.)

Why the big investment in L.A.?

Los Angeles is one of the nation’s top domestic markets for corporate travel, said Bob Cortelyou, Delta’s senior vice president for network planning.

“The economy is strong, and it’s time for us to take advantage and expand the Delta experience in Los Angeles,” he said.

LAX is already in the midst of a $4.1-billion modernization, which includes an expansion of the Tom Bradley International Terminal and 18 new gates for international passengers. Work is expected to be completed in 2014.